1. Field of the Invention
This invention is concerned with permanent-magnet material of samarium, cobalt, copper and iron, a method of producing such material and an application for it.
2. Description of the Prior Art
Material of the aforementioned type has been described for example by H. Senno and Y. Tawara in IEEE Transactions on Magnetics, Vol. 10, No. 2, June 1974, p. 313 ff., and is also known from DT-OS 2,406,782. According to these references Sm Ce Co Fe Cu- alloys especially those within the 1-5 to 2-17 composition range are distinguished by a high coercive force .sub.I H.sub.c and good remanence B.sub.r with an improved energy product (BH).sub.max as compared to exclusively copper-hardened SmCo-magnetic material. These good characteristics are obtained by the addition of cerium and iron to the Sm Co Cu- alloys, but are dependent to a great extent, however, on the amount of cerium added and on the proportion of it with respect to the cobalt, copper and iron. As a result, these alloys are not entirely satisfactory.